Mechanisms for N-Type Impurity-Induced Disordering of AlGaAs/GaAs Superlattices

1992 ◽  
Vol 262 ◽  
Author(s):  
B. L. Olmsted ◽  
S. N. Houde-Walter ◽  
R. Enrique Viturro

ABSTRACTWe report on a study of disordering by the in-diffusion of a variety of Group IV and Group VI n-type impurities. Secondary ion mass spectroscopy, electrochemical C-V profiling, photoluminescence spectroscopy, and cathodoluminescence spectroscopy were used to determine the extent of interdiffusion, and the spatial distribution of impurities and native defects for impurity-induced disordering. In all cases, the n-type dopants enhance the Al-Ga interdiffusion coefficient over that due to an As overpressure of 2 atm alone. The Si-induced enhancement has been previously attributed to the change in Fermi level with doping and therefore should account for disordering using other n-type impurities. However, we observe important differences in the interdiffusion characteristics (diffusion rate, dopant profiles, energy and intensity of the deep-level emission) induced by Si or Ge, and that by S or Se. Whereas a strong correlation exists between the carrier concentration profile and the disordered regions in the Si-, Ge-, and Se-doped crystals, little direct correspondence is found for crystals doped with S. Instead, the disordering seems to be determined primarily by the presence of Group III vacancies, as is also the case in undoped crystals disordered by an As ambient alone. In addition, the deep level emission at 1.15 and 1.3 eV, which are associated with vacancy defects, correlates well with the extent of the Al-Ga interdiffusion.

2013 ◽  
Vol 57 (2) ◽  
pp. 209-217 ◽  
Author(s):  
Dariusz Bednarek ◽  
Katarzyna Dudek ◽  
Krzysztof Kwiatek ◽  
Małgorzata Świątkiewicz ◽  
Sylwester Świątkiewicz ◽  
...  

Abstract The aim of the study was to evaluate the immune effects of genetically modified (GM), insect resistant corn (MON810) expressing toxin protein of Bacillus thuringiensis, and glyphosate-tolerant soybean meal (Roundup Ready MON-40-30-2), which are used as the feed mixture components in domestic animals. The study was conducted on 60 pigs (36 fatteners and 24 sows), 20 calves, 40 broilers, and 40 laying hens. Each species was divided into four basic nutritional groups: group I (control) - conventional feed, group II - feed consisted of GM soybean meal and non-modified corn, group III - non-modified soybean meal and GM corn, group IV - GM soybean meal and GM corn. Moreover, in the experiment on fatteners two additional groups were formed: group V - animals fed both conventional soybean meal and bruised grain, and group VI - GM soybean meal and conventional bruised grain. The results of study did not reveal any significant effect of feed mixtures containing GM components on the immune response in all animals regardless of their species and technological producing groups.


2020 ◽  
Vol 8 (02) ◽  
pp. 55-59
Author(s):  
Reetu Arora ◽  
Yogesh Kumar ◽  
Neetu Jindal ◽  
Renu Aggarwal ◽  
Kavneet Takhar

Abstract Introduction The aim of obturation in the root canal is to completely seal the canal space to eliminate all the portals of entry and exit between root canal and periodontal space. Various techniques have been developed to achieve a hermetic seal. Materials and Methods As many as 150 extracted human maxillary central incisors were taken for the study. Biomechanical preparation was done up to F5 protaper file. According to different obturation techniques, samples were divided into six groups, keeping 30 samples in experimental and 15 samples in control groups. Group I–Lateral Condensation, Group II–Thermafil, Group III–Beefill, Group IV–GuttaFlow, Group V–Positive Control group, Group VI–Negative Control group. After obturation, the samples were immersed in 2% Rhodamine-B dye for 24 hours. Each sample was longitudinally sectioned to examine under confocal laser scanning microscope. Statistical Analysis The results were evaluated with ANOVA and posthoc Tukey honest significant difference (HSD) comparison test. Results The mean values of dye penetration of different groups were Group I (Lateral Condensation) 1.51 ± 0.451, Group II (Thermafil) 0.918 ± 0.399, Group III (Beefill) 1.30 ± 0.559. Group IV (GuttaFlow) 0.655 ± 0.396, Group V (Positive Control group) 1.96 ±0.046, Group VI (Negative Control group) 0 ± 0. The lowest mean value of apical microleakage was found in GuttaFlow amongst all experimental groups. Conclusion It can be concluded that the GuttaFlow obturating material exhibited better apical sealing ability with canal walls.


2019 ◽  
pp. 39-42
Author(s):  
G.Yu. BEREZKINA ◽  
S.L. VOROBYEVA ◽  
E.M. KISLYAKOVA ◽  
A.A. KOREPANOVA

Изучено влияние возраста и живой массы при первом осеменении на воспроизводительные качества коровпервотелок чернопестрой породы в племенных заводах Удмуртской Республики. Исследования проводились в период с 2015 по 2018 гг. Для проведения исследований были сформированы 6 групп животных в зависимости от возраста первого осеменения. В I группу вошли коровы с возрастом первого осеменения до 13 мес, во II от 13,1 до 15 мес, в III от 15,1 до 17, в IV от 17,1 до 19, в V от 19,1 до 21 и в VI группу от 21 мес и старше. При этом живая масса телок в I группе в среднем составила 349,5 кг, во II 370,9, в III 387,7, в IV 400,2, в V 420,7 и в VI группе 440,2 кг. Анализ возраста первого осеменения в племенных хозяйствах республики показал, что средний возраст плодотворного осеменения в 2018 году составил 17,0 мес. с живой массой 394 кг. По результатам экспериментальных исследований нами получено, что лучшие воспроизводительные показатели и молочная продуктивность выявлена у коровпервотелок, которых осеменяли в возрасте 14,6 мес. В данной группе продолжительность сервиспериода составила 127,3 дня, коэффициент воспроизводительной способности 0,90, выход телят на 100 коров составил более 85,3. Удой за 305 дней лактации, у коровпервотелок второй опытной группы составил 6332,3 кг с массовой долей жира 3,65 и белка 3,15 .The influence of age and live weight at the first insemination on reproductive qualities of cowsborn black and white breed in breeding farms of the Udmurt Republic was studied. The studies were conducted between 2015 and 2018. For the research 6 groups of animals were formed depending on the age of the first insemination. Group I included cows with the age of first insemination up to 13 months, in group II from 13.1 to 15 months, in III group from 15.1 to 17 months, in group IV from 17.1 to 19 months, in group V from 19.1 to 21 months and in VI group from 21 months and more. At the same time, the live weight of heifers in group I averaged 349.5 kg, in group II370.9 kg, in group III 387.7 kg, in group IV 400.2 kg, in group V 420.7 kg and in group VI 440.2 kg. The analysis of the age of the first insemination in breeding farms of the Republic showed that the average age of fruitful insemination in 2018 was 17.0 months with a live weight of 394 kg. According to the results of experimental studies, we obtained that the best reproductive performance and milk productivity was revealed in cows, which were inseminated at the age of 14.6 months. In this group, the duration of the service period was 127.3 days, the coefficient of reproductive capacity 0.90, yield of calves per 100 cows. Milk yield for 305 days of lactation, in cows of the second experimental group was 6332.3 kg with a mass fraction of fat 3.65 and protein 3.15.


1963 ◽  
Vol 20 (5) ◽  
pp. 1213-1230 ◽  
Author(s):  
Barry S. Muir

A small population of maskinonge was exploited by a 9-year fishery, using fixed nets under control of the investigator. During the period 1952 to 1960, approximately 4000 maskinonge were handled, 2000 of them being tagged and returned to the population.The rate of loss of the preopercular disc tag increased progressively with time out, so that an estimated 8.5% of the tags had been lost after the end of the first year, 30% after the second and virtually all after the third. The total mortality and tag loss is estimated to range from 25% to 66% during the period from spring to fall for various years. These estimates are used as correcting factors to determine the numbers of tags extant at the start of the fall fishery each year. The rates of recapture of these tags give estimates of exploitation during the fall fisheries, and the average coefficient of catchability, derived from these data, is 0.0026 for fish age IV and older.A method, using simultaneous tag and recapture data, is developed to estimate the coefficient of catchability for each age-group. The estimated coefficients of catchability increase, almost linearly, from 0.0013 for age-group III to 0.0032 for age-group VI+. The average coefficient estimated by this method, 0.0025 for age-group IV and older, agrees well with that estimated independently by the method above.


2019 ◽  
Vol 7 (5) ◽  
pp. 701-706 ◽  
Author(s):  
Vivi Sofia ◽  
Ellyza Nasrul ◽  
Menkher Manjas ◽  
Gusti Revilla

BACKGROUND: Therapy for osteoarthritis (OA) with satisfactory results has not been found to date. In OA pathogenesis, RELA gene involved in cartilage degradation and MMP-13 in degrade cartilage, as a member family of NF-ĸβ genes, RELA serves to modulate inflammatory responses and activates pro-inflammatory cytokines. AIM: This study aims to identify the influence of Wharton Jelly Mesenchymal Stem Cell (MSC-WJ) on MMP-13 and RELA expression gene in synoviocyte by in vitro. MATERIAL AND METHODS: This research is pure experimental research. The sample used derived from synovial tissue of OA patients who underwent Total Knee Replacement (TKR) surgery. This study was divided into six groups treated with 4 replications. Group I and II (control groups) were synoviocyte of OA incubated for 24 and 48 hours, respectively. Group III and IV were MSC-WJ incubated for 24 and 48 hours, respectively. Group V and VI were Synoviocyte-MSC-WJ co-culture group incubated for 24 and 48 hours, respectively. Identification of MMP-13 and RELA gene expression in each group was performed by using qPCR. RESULT: The results showed that MSC-WJ reduced MMP-13 gene expression after co-culture for 24 and 48 hours in OA synoviocyte. The highest gene expression of MMP-13 was in Group I and II (1.00 ng/μl), followed by Group III (0.41 ng/μl), Group IV (0.24 ng/μl), Group V (0.13 ng/μl), and Group VI (0.04 ng/μl). MSC-WJ administration also decreased RELA gene expression. The highest gene expression of RELA gene was in Group I and II (1.00 ng/μl), Group V (0.67 ng/μl), Group III (0.58 ng/μl), Group IV (0.16 ng/μl), and Group VI (0.16 ng/μl). CONCLUSION: This study concluded that MSC-WJ in OA synoviocyte significantly reduced the expression of MMP-13 and RELA gene (p <0.05).


2021 ◽  
Vol 11 (5) ◽  
pp. 865-874
Author(s):  
Yu. V. Bukina ◽  
N. N. Polishchuk ◽  
H. V. Bachurin ◽  
O. S. Cherkovska ◽  
O. L. Zinych ◽  
...  

The gut microbiome profoundly affects the body functioning: it participates in host protection against pathogenic microorganisms, metabolic events, inhibition of inflammatory responses, formation of innate and adaptive immune response in the intestinal mucosa. One of the causes altering microbiota community is due to antibiotics. Therefore, the processes of antibiotics interaction together with Salmonella enteritidis and Salmonella typhimurium with representatives of normal intestinal microflora are of particular interest. Materials and methods. The quantitative and qualitative analysis of the wall microbiota composition in rats was evaluated by bacteriological method, the statistical data analysis was performed using the software StatSoft Statistica v.12. Results and discussion. Inoculation of vancomycin and S. enteritidis, S. typhimurium in groups II, III, IV resulted in quantitatively decreased E. coli level by 10-, 7- and 110-fold, respectively (p ≤ 0.05). The count of P. aeruginosa decreased markedly only in the group III (p ≤ 0.05). The count of Bacteroides spp. members was profoundly decreased by several thousand times (group II) as well as 70- and 87-fold (groups III and IV), respectively (p ≤ 0.05). The count of E. faecalis and E. faecium decreased by 861-, 6- and several thousand times (groups II, III, IV), respectively (p ≤ 0.05). The count of Proteus spp. markedly decreased in group II by 27-fold and rapidly increased in group IV (p ≤ 0.05). Group III revealed a sharp decline in level of Enterobacter spp. and Klebsiella spp. by 847- and 150-fold, whereas in group II they were increased by 7- and 46-fold, respectively (p ≤ 0.05). The count of Staphylococcus spp. decreased by 10-fold only in group II. The level of Clostridium spp. decreased by several thousand times (group II) and by 5,500 times (group IV) (p ≤ 0.05). The count of Lactobacillus spp. decreased by several thousand times (group II). The count of Bifidobacterium spp. members significantly decreased by 10.9-fold and by several thousand times (groups III, IV). The level of Peptostreptococcus anaerobius profoundly decreased in all three study groups (p ≤ 0.05). The level of Salmonella spp. increased in group II by 49 times, but markedly increased in groups III and IV (p ≤ 0.05). Inoculation of Salmonella after vancomycin pretreatment caused dramatic change in the microbiota composition in groups V and VI, namely: increased count of E. coli by 65- and 105-fold, markedly increased level of P. aeruginosa in group V and VI — by 3-fold. In addition, these groups also showed decreased level of Bacteroides spp. by 9- and 10-fold (p ≤ 0.05). The count of E. faecalis and E. faecium decreased dramatically only in group V (p ≤ 0.05). The count of Proteus spp. decreased by 17 times in group V as well as in group VI (p ≤ 0.05). A sharp increase in level of Enterobacter spp. and Klebsiella spp. members was observed in groups V and VI (p ≤ 0.05). However, representatives of Peptostreptococcus anaerobius in groups V and VI decreased by 20 and 9 times, respectively (p ≤ 0.05). The count of Salmonella spp. decreased only in group V by 7 times (p ≤ 0,05). Inoculating experimental animals with B. fragilis conditioned with S. enteritidis, S. typhimurium and pretreated with vancomycin resulted in markedly decreased level of E. coli in group VII and VIII by 538 times (p ≤ 0.05). The count of P. aeruginosa in groups VII and VIII decreased profoundly, whereas level of Bacteroides spp. members was reciprocally increased (p ≤ 0.05). The level of Lactobacillus spp. decreased by 10.3 times only in group VI. The count of E. faecalis and E. faecium increased by 10 and 19 times in groups VII and VIII, respectively, whereas level of Proteus spp. decreased only in group VII by 322 times (p ≤ 0.05). In addition, a sharp decrease in level of Enterobacter spp. and Klebsiella spp. members (p ≤ 0.05) was found in groups VII and VIII. The count of Peptostreptococcus anaerobius and Lactobacillus spp. members was markedly increased by 7-, 12-, several thousand-fold and 40 times (groups VII and VIII, respectively) (p ≤ 0.05). The count of S. enteritidis and S. typhimurium in groups VII and VIII decreased rapidly (p ≤ 0.05). Conclusion. Inoculation of B. fragilis can be used in treatment of inflammatory bowel diseases or disorders with impaired gut barrier function.


Author(s):  
M.M. Melo ◽  
G.G. Habermehl ◽  
N.J.F. Oliveira ◽  
E.F. Nascimento ◽  
M.M.B. Santos ◽  
...  

It was investigated the efficiency of two extracts of plants and one fraction of their properties against the local effects of bothropic envenomation. Bothrops alternatus venom (1.25µg) diluted in 100µl of sterile saline solution was inoculated (intradermally) into the shaved dorsal back skin of 30 New Zealand rabbits. The animals were divided in six groups receiving the following treatments: group I: subcutaneous application of Curcuma longa extract (1.0ml); group II: topic treatment of Curcuma longa hydroalcoholic extract (1.0ml); group III: topic application of ar-turmerone in vaseline (1.0g); group IV: topic application of Curcuma longa methanolic extract (1.0ml); group V: topic application of Calendula officinalis ointment (1.0g); group VI: topic application of saline (1.0ml). These treatments were done at 30 minutes, and at 2, 4, 24 and 72 hours after venom inoculation. Intensity of local edema, hemorrhagic halo and necrosis were evaluated until 168h after that. Additionally, seven days after the Bothrops venom inoculation, blood was collected from heart with and without EDTA (10%) for hemogram and biochemical parameters (total protein, blood urea nitrogen, creatinine, and fibrinogen) and all the animals were anesthetized, sacrificed by ether inhalation and submitted to necropsy. Fragments of tissues were taken for histopathological evaluation. The most efficient treatment for inhibition of edema, necrosis and local hemorrhage after Bothrops alternatus venom was the topic application of ar-turmerone.


2010 ◽  
Vol 04 (03) ◽  
pp. 257-262 ◽  
Author(s):  
Oral Sokucu ◽  
Seyda Herguner Siso ◽  
Firat Ozturk ◽  
Ruhi Nalcaci

Objectives: The aim of this study was to compare the shear bond strength (SBS) of two different light sources under different thermal cycle frequencies.Methods: Ninety human premolar teeth were divided into six groups, in which three groups consisted of halogen groups – Group I was cured with halogen without thermocycle, Group II cured with halogen with 500 thermocycles, and Group III cured with halogen with 10,000 thermocycles. The other three groups consisted of Plasma arc (PAC) group – Group IV was cured with PAC without thermocycle, Group V cured with PAC thermocycled 500 cycles, and Group VI cured with PAC thermocycled 10,000 cycles. Two way ANOVA was used to compare the SBS between the groups, and chi squaretest was used to compare the bond failure of ARI scores among the groups.Results: A significant difference was found for curing lights (P<.001) and thermocycling (P<.01). However, there was no interaction between light curing and thermocycling (P=.177). The halogen groups demonstrated higher mean SBS than the PAC groups. Both groups showed a significant reduction between no cycles and 10,000 cycles (P<.05).Conclusions: Both light sources showed favorable SBS performance without the thermocycle procedure. Thermocycling significantly decreased the SBS values of both groups. (Eur J Dent 2010;4:257- 262)


2021 ◽  
Vol 273 ◽  
pp. 02020
Author(s):  
Olga Tretyakova ◽  
Valentina Nefyodova ◽  
Victoria Solonnikova ◽  
Svetlana Romantsova

The influence of the age of the first insemination of pigs on their subsequent productivity was evaluated. In the period from 2017 to 2020, 167 pigs were inseminated in the company Plemzavod-Yubileyny in the Tyumen region, which were divided into groups. Productivity indicators were analyzed based on the number of piglets born. In 2017, 12.5 piglets were obtained in group III, where the age of the first insemination was 241-253 days, and 12.7 piglets were obtained in group VI (281-311 days). In 2018, 101 sows were farrowed out of 164 heads (groups I, II, III), 1123 piglets were received from them, 1037 live ones were received. The largest number of piglets born was observed in group IV-12.4 units. In 2019, the largest number of piglets born was observed in group III-11.4 units. In 2020, out of 181 farrowings, 135 units were received, of which 1,528 piglets, of which 1,507.5 live.


INDIAN DRUGS ◽  
2018 ◽  
Vol 55 (12) ◽  
pp. 69-77
Author(s):  
A. K Srivastava ◽  
◽  
D Kaushik ◽  
V. K. Lal

The present study was undertaken to develop a method and to assess the anti-stress activity of poly herbal formulation HAF-I & HAF-II in immobilised stress induced rat model. Acute toxicity study was performed according to OECD guidelines No. 423. Sprague Dawley female rats were observed periodically for the symptoms of toxicity and death within 24 h and at regular intervals for 14 d. In anti-stress study, total 24 female rats were selected and divided into four groups of six animals each. The stress was confirmed by physiological parameters as well as malonaldialdehyde and FOX1 level measured in the blood samples of 18 animals. On the basis of these parameters, treatments were started in group III to group VI animals taken individually dose of 200 mg/kg body weight daily dose per oral administration. Our finding showed that there were significant (P<0.0001) increased MDA, FOX1 and AChE enzyme activities along with decreased (P<0.0001, P<0.001) catalase, glutathione and total thiol antioxidant enzymes levels in stress induced group as compared to control group. After treatment with respective poly-herbal drugs HAF-I & HAF-II in group III to group IV animals, these above parameters were significantly improved in all treated animals after 20 days. Based on above study, it is concluded that these poly herbal formulations are effective for management of stress but comparativly, HAF-I is more effective for the improvement of stress (MDA, FOX1, AChE) levels and anti-oxidant enzyme during stress.


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